package com.itheima.reggie.filter;


import com.alibaba.fastjson.JSON;
import com.itheima.reggie.common.BaseContext;
import com.itheima.reggie.common.Result;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否已经完成登录
 */
//          过滤器名字                          拦截哪些路径
@WebFilter(filterName = "loginCheckFilter", urlPatterns = "/*")
@Slf4j
/*
实现过滤器接口
 */
public class LoginCheckFilter implements Filter {
    //路径匹配器 支持通配符 专门进行路径匹配
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {

        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;


        //1.获取本次请求的uri
        String requestURI = request.getRequestURI();

        //日志记录 拦截路径
        log.info("拦截到请求: {}", request.getRequestURI());


        //定义不需要处理的请求路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/user/sendMsg",
                "/user/login"

        };

        //2.判断本次请求是否需要处理
        boolean res = check(requestURI, urls);
        //3.如果不需要处理 则直放行
        if (res) {
            log.info("本次请求{}不需要处理",requestURI);
            filterChain.doFilter(request, response);
            return;
        }
        //4.判断登录状态 如果已经登录 则直接放行
        if (request.getSession().getAttribute("employee") != null) {
            log.info("用户已登录, 用户id为:{}",request.getSession().getAttribute("employee"));

            Long empId = (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);

            filterChain.doFilter(request, response);
            return;
        }

        //4.2 判断登录状态 如果已登录 则直接放行
        if (request.getSession().getAttribute("user") != null) {
            log.info("用户已登录, 用户id为:{}",request.getSession().getAttribute("user"));

            Long userId = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);

            filterChain.doFilter(request, response);
            return;
        }
        //5.如果未登录 则返回未登录结果 ,通过输出流的方式向客户端页面响应数据
        //装换成json字符串
        response.getWriter().write(JSON.toJSONString(Result.success("NOTLOGIN")));
        return;

    }

    /**
     * 路径匹配 检查本次请是否需要放行
     *
     * @param requestURI
     * @param urls
     * @return
     */
    public boolean check(String requestURI, String[] urls) {
        for (String url : urls) {
            boolean res = PATH_MATCHER.match(url, requestURI);
            if (res) {
                return true;
            }
        }
        return false;
    }
}
